Endocrine Abstracts

Section 1: Case history: A 46 year old man with Becker Muscular Dystrophy (BMD), was admitted with palpitations and shortness of breath. He had a past medial history of severe left ventricular dysfunction (LVSD) and cardiac arrhythmias, including atrial fibrillation (AF) treated with amiodarone, and an implantable cardiac defibrillator (ICD) for non-sustained ventricular tachycardia (VT). He had been treated with 3 months of prednisolone for suspected type 2 amiodarone induced thyroiditis. His baseline mobility had declined in recent years, but he mobilised at home with a stick and outside with a mobility scooter.

Section 2: Investigations: Cardiac monitoring revealed short non-sustained VT and interrogation of the ICD showed AF with fast ventricular response for which 18 shocks from the ICD had been delivered. Chest radiograph showed acute pulmonary oedema and echocardiogram confirmed severe LVSD. The cardiac arrhythmias and cardiac decompensation were driven by severely deranged thyroid function with T4 of 89 pmol/l (acutely rising from 30pmol/l) and TSH <0.01. He scored over 45 on the Burch Wartofsky scale, confirming an acute thyroid storm.

Section 3: Results and treatment: The acute pulmonary oedema resolved with intravenous (IV) glyceryl trinitrate, IV furosemide and continuous positive pressure ventilation (CPAP). The AF/VT storm failed to resolve with IV amiodarone, bisoprolol, ivabradine, overdrive pacing, and direct current cardioversion (DCCV). He subsequently had 3 short episodes of pulseless VT requiring cardiopulmonary resuscitation and shocks. VT ablation was deemed too high risk and the cardiothoracic multidisciplinary deemed him unsuitable for cardiac transplantation. The thyroid storm failed to resolve with carbimazole followed by maximal endocrine therapy comprising propylthiouracil, lithium and cholestyramine, and the thyrotoxicosis had deteriorated despite 3 months of high-dose prednisolone. Total thyroidectomy was deemed the only definitive solution to resolve the thyrotoxicosis, and facilitate ongoing use of amiodarone for the cardiac arrhythmias, but definitive cardiac stabilisation was necessary beforehand. AV node ablation with CRTD was therefore successfully completed. An open total thyroidectomy was performed with no immediate or acute complications. He received peri- and post-operative hydrocortisone for adrenal suppression, which was optimised post-operatively due to hypotension. He was discharged home at his functional baseline.

Section 4: Conclusions and points for discussion: This case depicts exemplary multidisciplinary team working with the endocrinologists, cardiologists, and surgeons, to perform a total thyroidectomy with an excellent post-operative outcome, in a high-risk surgical candidate. Life expectancy in BMD is 40-50 years, highlighting the remarkable outcome achieved in this case.